Phenoxaphosphinic acid derivatives

ABSTRACT

Phenoxaphosphinic acid derivatives corresponding to the formula   WHEREIN R represents chloro, bromo, lower alkyl or lower alkoxy and X represents morpholino. The compounds are useful as pesticides for the control of plant pests.

United States Patent [191 Strycker Jan. 30, 1973 [54] PHENOXAPHOSPHINIC ACID DERIVATIVES [75] Inventor: Stanley J. Strycker, lvfidla ndtMich.

[73] Assignee: The Dow Chemical Company, Midland, Mich.

[22] Filed: May 25,1970

[21] App]. No.: 48,693

Related U.S. Application Data [62] Division of Ser. No. 764,913, Oct. 3, I968, Pat. No.

OTHER PUBLICATIONS Campbell J. Chem. Soc. C, 1968, pages 3026-3028,

precise date unknown. Granoth et al., Israel J. of Chemistry Vol. 6 (1968), Sept-Oct. pages 65 l657.

Primary ExaminerAleX Mazel Assistant Examiner-Jose Tovar Attorney-Griswold & Burdick, Theodore Post and John L. Spalding [57] ABSTRACT Phenoxaphosphinic acid derivatives corresponding to the formula wherein R represents chloro, bromo, lower alk-yl or lower alkoxy and X represents morpholino. The compounds are useful as pesticides for the control of plant pests.

2 Claims, No Drawings PHENOXAPI-IOSPHINIC ACID DERIVATIVES This application is a division of U. S. patent application Ser. No. 764,913, filed /3/68 now U. S. Pat. No. 3,576,863.

SUMMARY OF THE INVENTION The present invention concerns a group of new phenoxaphosphinic acid derivatives corresponding to the formula 6 1 l U B 2 R 10 R. 9 1 O X In this and succeeding formulas, R represents chloro, bromo, lower alkyl or lower alkoxy and X represents morpholino phine lO-oxide, 2,8-di-n-propoxy-l0- morpholinophenoxaphosphine l0-oxide, 2 ,8-di-nbutyl-l O-(phenylthio)phenoxaphosphine l0-oxide,

2,8-diethoxy-l 0-( phenylthio )phenoxaphosphine l0- oxide and 2,8-di-n-butoxy-l0-(phenylthio)phenoxaphosphine lO-oxide.

The new phenoxaphosphinic acid derivatives are prepared by reacting a 2,8-disubstituted phenoxa-phosphinyl chloride with l-IX when HX is morpholine according to the following mechanism:

The reaction is conveniently carried out in an inert organic solvent as reaction medium, such as benzene, toluene, xylene, methylene chloride, tetrahydrofuran, ether, dioxane, 1,2-dimethoxyethane or mixtures thereof. The amounts of the reagents to be employed are not critical, some of the desired product being obtained when employing any proportions of the reactants. However, the reaction consumes the reactants in equimolar proportions and such proportions are generally preferred. The reaction proceeds at a hydrogen chloride or chloride liberating temperature, conveniently at temperatures between 50 and 150C. and preferably at the boiling temperature. A hydrogen chloride acceptor such as triethylamine, pyridine, potassium carbonate or N,N-dimethylaniline is added to the reaction medium if desired, and is preferable when I-IX is allylamine or morpholine.

In preparing the compounds of this invention morpholine, the reactants and reaction medium are contacted in any convenient order. Following the contacting of the reactants, the temperature of the reaction mixture is maintained within the reaction temperature range for a short period of time. After the reaction period, the desired product can be separated and collected by conventional procedures such as crystallization and decantation or filtration. The new phenoxaphosphinic acid derivatives thus isolated can be employed in pesticidal applications or further purified by conventional procedures such as washing and crystallization before being so employed.

DESCRIPTION OF THE PREFERRED EMBODIMENTS EXAMPLE I l0-ALLYLAMlNO-2,8- DIMETHYLPHENOXAPHOSPHINE IO-OXIDE To a stirred partial solution of 5.58 g. (0.02 mole) of 2,8-dimethylphenoxaphosphinyl chloride in ml. of l,2-dimethoxyethane was added rapidly a solution of l.l4 g. (0.02 mole) of allylamine and 2.29 (0.022 mole) of triethylamine in 40 ml. of l,2-dimethoxyethane. The addition was carried out at room temperature and was complete in 10 minutes. The resulting mixture, containing a white precipitate, was then warmed slightly and filtered. The residual salt was washed well with several portions of warm 1,2- dimethoxyethane. The residue on evaporation of the 1,2-dimethoxyethane liquors was recrystallized from ml. of the same solvent to give the title compound as nearly colorless crystals, melting at l35-l38C. A sample recrystallized once again melting at l36-l39 C.

The procedure is repeated with the substitution of morpholine in place of allylamino to give the corresponding lO-morpholino derivative.

2,8-DIMETHOXY- l 0- PHENYLTHlOPI-IENOXAPHOSPHINE lO-OXIDE A stirred partial solution of 3.11 (0.01 mole) of 2,8- dimethoxyphenoxaphosphinyl chloride in 50 ml. of toluene was treated with 1.10 g. (0.01 mole) of thiophenol in 50 ml. of toluene at room temperature. Subsequently, the reaction mixture was heated at reflux for a period of one hour, filtered hot and allowed to cool to room temperature. The product separated as colorless Crystalline C H OJS, having a molecular weight of 384.38.

EXAMPLE 2 2,8-DlCHLORO-l- MORPHOLINOPHENOXAPHOSPHINE IO-OXIDE To a stirred partial solution of 6.38 g. (0.02 mole) of 2,8-dichlorophenoxaphosphinyl chloride in 100 ml. of l,2-dimethoxyethane was added a solution of 1.91 g. (0.022 mole) of morpholine and 2.2 g. (0.022 mole) pf triethylamine in 50 ml. of 1,2-dimethoxyethane. The addition was carried out at room temperature followed by a 2-hour period of heating at 60-70C. The reaction mixture was filtered warm to remove the triethylamine hydrochloride which had separated. Evaporation of the solvent gave the product as colorless crystals which were subsequently purified by recrystallization from cyclohexane to give product C H Cl No P, having a molecular weight of 370.17.

I A substitution of 2,8-dibromophenoxaphosphinyl chloride for the 2,8-dichloro reagent gives the corresponding 2,8-dibromo compound.

The following compounds of the present invention are prepared following procedures described above.

2,8-dimethyl -morpholinophenoxaphosphine l0- oxide (melting at l65l68",C.) by reacting together 2,8-dimethylphenoxaphosphinyl chloride and morpholine.

2,8-di-n-propyll O-m orpholinophenoxaphosphine l0-oxide (molecular weight 385.43) by reacting together 2,8-di-n-propylphenoxaphosphinyl chloride and morpholine.

2,8-diethoxyl 0-morpholinophenoxaphosphine 10- oxide (molecular. weight 389.38) by reacting together 2,8-diethoxyphenoxaphosphinyl chloride and morpholine. v

2,8-dibromol O-morpholinophenoxaphosphine l0- oxide (molecular weight 459.10) by reacting together 2,8dibromophenoxaphosphinyl chloride and morpholine.

The compounds of the present invention or compositions containing the same are useful as pesticides. For the control of insect and plant pests including bacteria and fungi, the compounds or compositions containing them can be applied to pests and their habitats in pesticidal amounts to obtain adequate controls and kills. Such pests can be controlled as the two-spotted spider mite, American cockroach, alfalfa, lettuce downy mildew, tomato late blight, acid fast bacterium, fungus rhizoctonia solani, Trichophyton mentagrophytes, Staphylococcus aureus and Bacillus subtilis. This is not to imply that all of the compounds herein are equally effective against the same organisms or at the sameconcentrations.

The compounds conveniently can be employed in liquid or dust compositions. In such usage, the compounds 'are modified with one or a plurality of adjuvants or helpers including water, organic solvents, petroleum oils, petroleum distillates, naphthas, or other liquid carriers, surface active dispersing agents and finely divided solids such as chalk, talc or bentonite. Depending upon the concentration of the toxicant compounds in such formulations, the augmented compositions are adapted to be distributed on plants or plant parts, or in soil, inks, adhesives, cutting oils, paints, textiles, paper, lumber, white or cooling waters, or to be employed as concentrates and subsequently diluted with additional liquid or solid adjuvants to The exact concentration of the novel compounds to be employed in the treating compositions is not critical and may vary considerably provided the required amount of effective agent is supplied on the plant or plant part, in the soil, ink, adhesive, cutting oil, textile, paper, wood and so forth. The concentration of toxicant in liquid compositions generally'is from about 0.05 to 50 percent by weight. Concentration up to percent by weight oftentimes are conveniently employed. in dusts, the concentration of the toxicant can be from about 0.05 to 10 percent by weight. In compositions to be employed as concentrates, the toxicant can be present in a concentration of from 5 to 98 percent by weight.

In operations against soil dwelling pests such as soil fungi and bacteria, the compounds of the present invention are effective in the killing of such organisms at concentrations of 500 parts per million be weight of soil. When employed as the active constituent against bacterial and fungal diseases of plants, the compounds are effective at concentrations of 1,500 parts per million by weight. In other operations, the compounds of the present invention are effective in preventing the microbial degradation of wood when the wood is impregnated with liquid compositions containing the toxic compounds of this invention at concentrations of 10,000 parts per million byweight. in addition, the compounds of the present invention are useful for the control of terrestrial plants when employed at application rates of 100 pounds per acre. in still further operations, the compounds of the present invention are em ployed in paints, cutting oils white or cooling waters, casein suspensions or adhesives at a concentration of at least 1,500 parts per million by weight to achieve kill and control of fungi and bacteria which cause microbiological degradation of these products.

In representative operations, and 2,8-dimethyl-l0- morpholinophenoxaphosphine l0-oxide give complete control of alfalfa, lettuce downy mildew and tomato late blight when the compound is employed in aqueous compositions at a concentration of 50 pounds per acre in the first instance as a pre-emergent herbicide and at a concentraticTn of 2,000 parts per million in the second instance, as a foliar fungicide.

In further operations, and 2,8-dimethyll0- morpholinophenoxaphosphine l0-oxide give complete control of acid fast bacterium and fungus rhizoctonia solani when the compound is employed in aqueous compositions at a concentration of 500 parts per million both as bactericide and as fungicide.

The 2,8-disubstituted phenoxaphosphinyl chlorides required as starting materials for these reactions are prepared by reacting one of the corresponding 2,8-disubstituted phenoxaphosphinic acids with thionyl chloride wherein a chloro group replaces the acidic hydroxyl group in a conventional manner. The procedure for the synthesis of the phosphinic acids is based on that described by L. D. Freedman, G. O. Doak and J. R. Edmisten, J; Org. Chem. 26, 284

wherein R represents chloro, bromo, lower alkyl or lower alkoxy and X represents morpholino.

2. The compound of claim 1 wherein R represents methyl and X represents morpholino. 

1. A phenoxaphosphinic acid derivative corresponding to the formula 